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Full text of "The Morphology And Evolution Of The Apes And Man"

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THE  NERVOUS  SYSTEM
313
Chimpanzee
Gorilla
Superficial Plexus (S.C.P.)      Supei jlcial Plexus 1. Cardiac branch of left i  1. Cardiac branch
vagus
Deep Plexus (D.C.P.)
1.  Filaments    from    left j  1
sympathetic
2.  Thoracic branch of left
vagus                            2.
3.  Cervical branch of right
vagus
4.  Thoracic   branches   of
right vagus
5.  Branches   from   right
cervical sympathetic
6.  Branch from left recur-
rent laryngeal nerve
of left vagus
Deep Plexus
Filaments from right sympathetic
Branches o f right vagus
Branch from the left recurrent nerve
Man
Superficial Plexus
1.  Upper left cardiac
sympathetic nerve
2.  Lower cervical car-
diac branch of left vagus Ueep Plexus
1.  All cervical cardiac
branches of sympathetic except the upper left branch
2.  All cardiac branches
of the vagi except the lower left cervical one
3.  Branches   of   both
recurrent nerves
The superficial plexus is placed as in Man, but the deep plexus is higher up about the innominate artery. In Man the conditions, particularly the sympathetic contributions to the plexuses, are more complex. In the Apes, as in many lower mammals, the vagus probably conveys many sympathetic filaments.
The anterior pulmonary plexuses are formed by branches of the vagus nerves, and the posterior pulmonary plexuses are formed by twigs from the vagus nerves and upper thoracic sympathetic ganglia.
Solar Plexus,—In the Chimpanzee (fig. 53) the annular left cceliac ganglion receives the greater part of the right vagus nerve, and each coeliac ganglion receives a great splanchnic nerve. The two ganglia are united by communicating filaments ; and the plexus gives off the following plexuses :—
1. Communicating to the gangliated sympathetic cords (A.GLC.).